Current sealants are limited in use to temperature below 600.degree. F. because of their high organic molecular content. Such sealants also commonly use solvents in their processing or in their application to the surfaces to be sealed. Further, current sealants degrade as their surrounding temperatures increase and tend to perform less effectively as the temperature of clamping systems to which they are commonly applied increase. Still further, to be effective,current sealants require relatively thick application to the surfaces they are sealing and do not function adequately if the surfaces are marred or scratched. Thus, there is a need for an improved sealant which overcomes the foregoing shortcomings of current sealants. The present invention satisfies such a need by providing a solventless silicon sealant which will seal to marred and scratched surfaces and which preforms effectively at and above 600.degree. F. and, in fact, improves in effectiveness as the temperature of the surrounding environment and clamping system increase.